Device Bus – Part 4 Ethernet Board

I decided to change XPortHub2 due to parts of the layout – I need to use SPI 1 for “Device Bus” due to speed on F405, but the paths was crossed with Ethernet SPI and USB, meaning I had high frequency signals close without any isolation. I decided to re-route that part and add the same Device Bus signals designed for the test board. It is hard to see the difference, but it’s a huge difference between 1.0 and 1.1 as this is.

I really would like to make this a 4 layer design, but a 2 layer PCB cost 5.- USD and a 4 layer 45.- USD, so it’s a lot of difference. I will go ahead with this + the Device Bus test board.

The SPI on this is supported by extra signals RPION, BUSON and MASTERON the save way as on the Test board, but I am only using SPI0 on RPI and operating directly from F405.

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